// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/download/save_item.h"

#include "base/logging.h"
#include "base/strings/string_util.h"
#include "content/browser/download/save_file.h"
#include "content/browser/download/save_file_manager.h"
#include "content/browser/download/save_package.h"
#include "content/public/browser/browser_thread.h"

namespace content {

namespace {

    SaveItemId GetNextSaveItemId()
    {
        static int g_next_save_item_id = 1;
        DCHECK_CURRENTLY_ON(BrowserThread::UI);
        return SaveItemId::FromUnsafeValue(g_next_save_item_id++);
    }

} // namespace

// Constructor for SaveItem when creating each saving job.
SaveItem::SaveItem(const GURL& url,
    const Referrer& referrer,
    SavePackage* package,
    SaveFileCreateInfo::SaveFileSource save_source,
    int frame_tree_node_id,
    int container_frame_tree_node_id)
    : save_item_id_(GetNextSaveItemId())
    , url_(url)
    , referrer_(referrer)
    , frame_tree_node_id_(frame_tree_node_id)
    , container_frame_tree_node_id_(container_frame_tree_node_id)
    , total_bytes_(0)
    , received_bytes_(0)
    , state_(WAIT_START)
    , is_success_(false)
    , save_source_(save_source)
    , package_(package)
{
    DCHECK(package);
}

SaveItem::~SaveItem() { }

// Set start state for save item.
void SaveItem::Start()
{
    DCHECK_EQ(state_, WAIT_START);
    state_ = IN_PROGRESS;
}

// If we've received more data than we were expecting (bad server info?),
// revert to 'unknown size mode'.
void SaveItem::UpdateSize(int64_t bytes_so_far)
{
    received_bytes_ = bytes_so_far;
    if (received_bytes_ >= total_bytes_)
        total_bytes_ = 0;
}

// Updates from the file thread may have been posted while this saving job
// was being canceled in the UI thread, so we'll accept them unless we're
// complete.
void SaveItem::Update(int64_t bytes_so_far)
{
    if (state_ != IN_PROGRESS) {
        NOTREACHED();
        return;
    }
    UpdateSize(bytes_so_far);
}

// Cancel this saving item job. If the job is not in progress, ignore
// this command. The SavePackage will each in-progress SaveItem's cancel
// when canceling whole saving page job.
void SaveItem::Cancel()
{
    // If item is in WAIT_START mode, which means no request has been sent.
    // So we need not to cancel it.
    if (state_ != IN_PROGRESS) {
        // Small downloads might be complete before method has a chance to run.
        return;
    }
    Finish(received_bytes_, false);
    state_ = CANCELED;
    package_->SaveCanceled(this);
}

// Set finish state for a save item
void SaveItem::Finish(int64_t size, bool is_success)
{
    DCHECK(has_final_name() || !is_success_);
    state_ = COMPLETE;
    is_success_ = is_success;
    UpdateSize(size);
}

void SaveItem::SetTargetPath(const base::FilePath& full_path)
{
    DCHECK(!full_path.empty());
    DCHECK(!has_final_name());
    full_path_ = full_path;
}

void SaveItem::SetTotalBytes(int64_t total_bytes)
{
    DCHECK_EQ(0, total_bytes_);
    total_bytes_ = total_bytes;
}

} // namespace content
